A Used EPIRB, a Leftover MMSI, and a Run to the Bahamas
Your 45-foot trawler is docked in Fort Lauderdale. In two weeks you will run to Bimini, then Nassau, returning three weeks later. Aboard: a DSC VHF, an AIS Class B transponder, and a 406 MHz EPIRB with GPS that you bought used from the previous owner, who left his MMSI programmed in the VHF and the AIS. Your brother-in-law, who holds no FCC credential of any kind, will stand night watches and may need to make radiotelephone calls to the Coast Guard or to a marina. The EPIRB's battery is in date, but its registration card is still in the previous owner's name. You hold a Marine Radio Operator Permit. There is no satellite phone aboard and no other radio equipment.
1. What authorizations and registrations must be in place before you clear the inlet, and who must hold what?
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Ship station license. An international voyage to a foreign port takes the station out of the domestic pleasure-craft accommodation and requires an FCC ship station license in your name. The license document goes aboard.
MMSI. For a vessel operating under an FCC ship station license, the MMSI is assigned as part of that license. That number - not the previous owner's - must be programmed consistently into the VHF, the AIS, and the EPIRB. A DSC radio and an AIS transponder disagreeing about who the vessel is defeats both systems.
EPIRB registration. Separate from the FCC license entirely. It is registered with NOAA, must name you as owner, describe this vessel, and carry a 24-hour shore contact who actually answers. The previous owner's card is worthless to a rescue coordination center looking for him while you are in the water.
Personnel. You hold the MROP, so the station can be operated. Your brother-in-law holding nothing is the weak point: either he obtains a permit before the trip, or the standing instruction is that he does not transmit unsupervised and wakes you for anything beyond answering a routine call. Decide which before you leave the dock, and write it down.
2. The previous owner's MMSI is already in all three devices. It is a valid number and everything powers up correctly. Why can't you just leave it, and what is the sequence to fix it?
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Why not: an MMSI is a station's identity, not a serial number. Leaving it in place means:
- A DSC distress alert or an AIS transmission from your vessel resolves in the rescue databases to a different boat, a different owner, and a different set of emergency contacts. Search assets go to the wrong place or to a vessel that is tied to a dock.
- Any DSC hail or AIS query intended for you goes to him.
- It is a false identification of the station - a regulatory violation independent of any accident.
- On an international voyage the number must be the one assigned to your licensed station; a number carried over from the previous owner's pleasure-craft assignment does not satisfy that.
Sequence: (1) obtain the ship station license; (2) take the MMSI from it; (3) reprogram the VHF, the AIS, and the EPIRB - several of these require a dealer or the manufacturer's software, so book that now, not the day before departure; (4) update the NOAA EPIRB registration with the new MMSI plus your contact details; (5) verify the VHF is actually receiving a live GPS position feed, so a distress alert carries a position rather than a prompt for one.
Judgement point: the fact that everything 'works' is exactly the trap. Every device is transmitting confidently and every one of them is wrong.